


Deductive Magic

by Roadstergal



Category: Harry Potter - J. K. Rowling, Sherlock (TV)
Genre: M/M
Language: English
Status: Completed
Published: 2011-03-22
Updated: 2011-03-22
Packaged: 2017-10-17 05:24:17
Rating: Mature
Warnings: Underage
Chapters: 4
Words: 7,572
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/173373
Author URL: https://archiveofourown.org/users/Roadstergal/pseuds/Roadstergal
Summary: <blockquote class="userstuff">
              <p>This fic came into being after I saw <a href="http://dauntingfire.deviantart.com/gallery/26624659#/d36zx50">this fanart</a>. It is set between the time of James Potter and Harry Potter at Hogwart's.</p>
            </blockquote>





	1. Arrival

Living in a fantasy world had rather a lot to recommend it; wasn't it the dream of every _normal_ kid? However, it did have one major disadvantage; namely, the person in change had a sense of taste that had been nurtured on three-strip Technicolor. When decisions on decor were left to Dumbledore, the result would invariably be brash and gaggingly tacky.

However, the food would be excellent.

To a fifteen-year-old boy, quality food in great quantity could make up for any number of sins, and so John grinned at the multicolored candles floating in the air and the gaudy drapes on the walls. The new students would be allowed in, they would be Sorted, and then there would be a massive feast.

Not that John would admit it, but he loved it when the new students arrived. So young, so eager - some shy, some brash, but all coming in to share in one of the most brilliant experiences on the planet, as far as he was concerned. This would be his fourth year, and his third time welcoming in new students, and he couldn't wait.

Out of the corner of his eye, he saw something fly towards his head; he instinctively shot up a hand, and intercepted a small, hard ball. A Feldmen's Flavor-Changing Fudge Roll, he noted, as Cox dropped down next to him on the bench. "Good arm, Watson - going to take Beater again this year?"

"What else?" John grinned. "Bloody good team this year, I think - we were just starting to come together last year..."

On John's other side, Loeffler leaned over, tugging at John's robe. "I've been practicing over the break," he hissed, quietly.

John looked around, quickly. "You could get in trouble for that," he whispered back.

"I couldn't go three months without touching a broom! But it's easy to get away with that when you have as many boys in the house as I do. Nobody would notice if I turned my head inside out..."

Cox hit John upside the head, and both of them turned towards the door. The new students were coming in.

John looked them over with interest. Such a variety... Hogwarts knew no distinctions of race, money, sex, or whatever else other schools might care about; it was all about the magic, and so the entrants were a rainbow hodgepodge of humanity. John, of course, looked for the girls. He was a fifteen-year-old boy, after all.

One child struck his eye immediately. Not a girl, but striking anyway - tall for his age, almost frighteningly skinny, bright blue-green eyes over razor-sharp cheekbones and under a mop of black hair that desperately needed a trim. Bright, aware eyes like that, his fearless, almost arrogant stance - Gryffindor, John was _sure_.

The hat sang its yearly song, and John noticed Fredric taking notes. He would no doubt have a brilliant parody written by the time the Sorting was done, and would sing it for them when they got back to their room. That blowhard Stephens would show the new Gryffindors around, and they'd have time to break out the gin that Cox kept on hand for special occasions and have some _proper_ fun before Stephens got back.

John grinned. He _loved_ Sorting.

Even when the bright-eyed boy was sorted to Slytherin. John felt oddly disappointed - after all, everyone knew that the Slytherins were evil.

* * *

John stood at attention in front of Dumbledore's desk, feeling rather important for being summoned by the man himself. After all, how often did _that_ happen? It can't have been for any particular achievement, though, he thought - after all, not much to mention had happened in the first month of classes. Oh, plenty John cared about, but nothing to take Dumbledore's interest, he was certain...

"John, my dear boy," Dumbledore said with a smile. "Have a sweet?" He held out a bowl of tempting-looking colorful candies, but John shook his head; his stomach was too knotted from excitement.

Dumbledore put the bowl back on the desk and sat back in his chair, still smiling genially. "My, how you've grown - it seems just yesterday you were a first-year, your eyes as big as saucers. Now - Beater, aren't you? You came so close to the Quidditch cup last year, I know you'll make another go this year. And Flitwick tells me you're _excellent_ in Charms."

"Thank you, sir." John wondered what Dumbledore had called him up for - it can't have been just for generic compliments?

"You must be wondering why I called you up here." Dumbledore's smile seemed almost sly. "I need your help, my dear boy."

"Whatever I can do," John replied, curiosity itching at his spine.

"Ah, yes - whatever you can do. You can do quite a lot, I know - perhaps more than you think, and more yet that you will find out." His eyes twinkled, and he waved his had dismissively. "That isn't important, however. I need your help with a first-year."

"All right," John responded, feeling a little let-down. Baby-sitting?

"This won't just be baby-sitting." Dumbledore's genial smile did not slip. "We have the good fortune this year of having a first-year who is... particularly gifted in academics. The introductory courses will not be sufficient. We tried to give him second-year curricula, but he simply soaked it all up in no time. He's ready for more advanced classes." Dumbledore nodded. "I would like you to take him with you."

"A first year? Taking fourth-year classes?" It was ridiculous. There was no way... John found himself poised between incredulity and... annoyance. _That_ smart? _Really?_

"Ah, now you see the problem. Mister Holmes is..." Dumbledore coughed, gently, "not the most socially adept of boys to start with, and this has the potential to cause some trouble. I want you to look after him. I know you can do it, and I know you will do both myself and your house proud."

John walked down the staircase, feeling a little put out. So this was what it was all about - babysitter to a petulant prodigy? He sighed, walking towards the Great Hall, where Dumbledore had told him to meet his new charge, Sherlock Holmes. He wondered if this could get any worse.

Upon entering the Great Hall, he realized that it could, indeed. The dour head of Slytherin, professor Snape, stood, waiting like a giant bat, his hands on the shoulders of the thin, dark-haired boy John had seen at the sorting ceremony. The Slytherin boy.

He was as tall as John, despite being four years younger, and he looked even taller as he stared at John with haughty arrogance. "So - you're the Gryffindor idiot."

* * *

"So, next is Charms," John said with a sigh, walking towards Flitwick's classroom.

The morning had been a choice slice of hell. Sherlock was simply impossible. Arrogant, insulting, condescending; John didn't have the vocabulary to properly encompass it, and might just settle for calling him 'an utter arsehole,' as Cox had.

The Gryffindors were all giving John a bit of room, which he didn't like. He had tried to explain to them that Dumbledore had saddled him with Holmes, but it's hard to properly communicate with your classmates when Snape is hovering over you like a dissolute vampire, ready to take points away for talking during class.

Holmes was, most definitely, brilliant. While John had started read the instructions methodically, ready to do the potions as he always did, step-by-careful-step, Holmes had snorted and yanked the book away, quickly rattling off the instructions as if he had the book memorized, setting John to preparing the ingredients, and lecturing him archly on how important it was to get the steps done rapidly, as the ingredients lost potency while just sitting around in prepared form. The Precipitation Potion had come out a perfect, shimmering blue, and it gathered a small thundercloud, complete with lightening, when Snape experimentally dropped a pinch on their table.

"Twenty points for Slytherin, for showing Gryffindor how to _properly_ make a potion," Snape had rumbled in his arch baritone. Cox had thrown a wadded piece of paper at John's head.

Cox and Loeffler had run off before John could catch them. He swore quietly to himself - he'd have to corner them at dinner and explain the situation.

"A little spat with your boyfriends?" Holmes had asked, his voice too deep for an 11-year-old, his face too arrogant for any member of the human race.

They settled down in their seats in Charms, and watched Flitwick demonstrate a HoloCharm; the diminutive professor generated a perfect three-dimensional figure of a bird. It flitted around the room, and John couldn't help reaching his hand out to touch it, experimentally, as it flew by; his fingers went right through it.

"Yes," Flitwick chirped, excitedly. "It's merely a semblance, a seeming, with no reality behind it. You saw that third gesture? That is the one that gives it form. Be sure to focus on your seeming with that move, and keep it in mind with that last flick, which brings it all back together with the bending of the light. Work with your partner!"

John fully expected to be humiliated again, but was rather surprised to note that Holmes did not have the same preternatural talent for Charms that he had for Potions. He feigned disinterest, but John could tell that the flat, robotic rabbit was the best he could do.

"The mind-picture you make with the third gesture has to have movement," John said, trying to be helpful. "Like..." He gestured, picturing a rabbit in his mind - its form, its shape, its soft fur and long ears, but also its wiggling nose, its shy nature, its quick, powerful kicks. It appeared before him with the final flick, glancing around nervously, running back and forth on their table.

"What a waste of time," Holmes snorted, tossing his wand on the table. "Really, all of this flicking and flitting and gesturing and... all that other bullshit, just to make a poxy fake rabbit. And you waste your time trying to do it _well_? I momentarily mistook you for someone with some modicum of intelligence."

"Be kind to your wand, Mr. Holmes," Flitwick replied, shaking his finger at Holmes as he walked past. He paused, looking at John's rabbit. "Brilliant work as usual, Mr. Watson!"

John grinned at Holmes, who rolled his eyes.


	2. Deduction

"So, how _are_ Slytherins at sucking cock?" Fredric asked, leaning in close as John sat on the ornate rug, trying to do his Potions homework. A bit too close for John's taste.

"Give it a rest, would you?" John sighed. "I told you, Dumbledore asked me to take care of him. What should I do, tell the _Headmaster_ that my friends don't want me to?"

"He didn't tell you to be _nice_ to the arsehole, did he?" Fredric snorted. "He's mean to you, you can damn well be mean to him back."

"He's not mean, he's just..." John tapped his quill on his paper, trying to think of the right phrase, "socially inept."

"He's a soulless bastard," Loeffler said with finality, dropping down next to John. "I heard from me older brother that _his_ brother was the same way. Mycroft? The bloke in the Ministry of Magic that nobody's sure what he does?"

"That made no sense," John grumbled, looking at his homework.

"I'll tell you what doesn't make sense," Fredric snorted, "is you letting your friends down in favor of that little twat. He'd better be one masterful cocksucker, is all I can say." He stormed out of the room.

"What's with him and sucking cock?" John rolled his eyes at Loeffler.

"Look," Loeffler sighed, running his hand through his mop of ginger hair, "I know you're trying to do the right thing because you're so fucking nice and dutiful and noble that you make the rest of us look like twats," he grinned, not unkindly, "but don't get so into this project of Dumbledore's that you forget your mates, eh?"

John grinned back. "Of course I won't. I don't hang out with the bloke, after all. And I've made all the practices, haven't I?"

"Yeah, we have a good team." Loeffler looked over his shoulder, making sure nobody was close enough to overhear, and dropped his voice. "Fredric wants to be starting Beater. That's one of the reasons he has a bug up his arse, truth be told."

"Well, he should come to the practices more often, shouldn't he," John replied, irritated.

"Yeah, you work harder and you're just plain better at it, we all know that. I'm just trying to say - he's been a little weird about it, you know?" Loeffler collected his books. "Dump those off and come to dinner. You know Holmes is just going to roll his eyes and give you the answers, anyway." He grinned and walked off towards his room.

* * *

The pageantry surrounding quidditch matches never failed to get John worked up. He remembered the first time he ever saw one - a professional match that Loeffler (then, just the goofy kid down the street) had taken him to. The crowds, the excitement, the banners, the men and women _flying around on broomsticks_! The golden snitch flitting out of the hands of Seekers, the thwack of wood on iron...

Of course, his parents told him that he should stop making up such crazy stories after Loeffler's family had been nice enough to take him to a cricket match (the owl really did end up taking them entirely by surprise). But when John had arrived at Hogwart's in his first year - he _knew_ that he had to play.

With his short stature, John had first tried to play Seeker, but he did not have the requisite quickness and nimbleness. His stocky build, however, made him an ideal Beater, and he had warmed to the position. And he had to admit, it was very cathartic - massively physical, intensely competitive. It left him both worn out and utterly fulfilled.

Today was the first match of the year - against Ravenclaw. The players lined up, facing each other, as the team captains met in the center of the pitch. Most of the players were known quantities, back from the year before; solid in their fundamentals, with intricate plays and excellent communication. They did have a new Seeker, a slender dark-skinned girl with her hair in a tight bun. John winked at her, and she rolled her eyes.

"Easy, boy," Loeffler chuckled, cuffing John. "We have a game to play!"

"Just get the snitch before she does," John replied, cinching his belt as they climbed aboard their brooms.

Madame Hooch looked at both sides, nodded to each captain, blew her whistle - and the game began.

There was no out-maneuvering Ravenclaw, and the Gryffindor team knew it. Ravenclaw had the finesse and the strategy, pulling defenders away with slick flying-work, passing the quaffle quickly and smoothly from one player to the other to pull defenders away from the goals. Gryffindor's only hope was to play _harder_ , and John dove in with a will, smashing bludgers in the direction of Ravenclaw players, making them take quick evasive action, disrupting their plays.

At one point, John saw a flash of gold out of the corner of his eye. The Snitch - but why were Loeffler and the Ravenclaw seeker all of the way on the other side of the pitch? And why was the Snitch flying at him so quickly...

The gold flash hit his shoulder, and he dropped his club with a yell as pain shot through his arm. It was startling enough that he almost fell off of his broom; he wrapped his right arm around the handle, looking behind him, his mind swimming with confusion. The gold flash was still there - and it doubled back, flying towards him again. Panicked, John looked down, wondering if he should dive - and saw his little Slytherin protege, Holmes, standing up in the spectator area and looking at John; his green-grey eyes were strangely intense. Holmes's lips moved, as if chanting - and pain shot through John's leg as the golden missile flew cleanly through it, leaving a ragged hole in its wake. John's eyes blurred as they teared up in reaction - and the missile exploded in a burst of light.

Gravity grabbed hold, and John felt air rush past his head. An arm grabbed his, slowing his descent, and he landed on the ground with a painful thud. "John, mate!" Loeffler gasped, not letting go, "are you all right?"

John grinned up at Loeffler's familiar, concerned face, and passed out.

* * *

John woke slowly, feeling soft covers on him and a soft bed - somewhat too soft, really - below him. He stirred, and his shoulder and leg grumbled at him with a dull ache.

"Oi, you're up?"

John opened his eyes to Loeffler's grinning face, his freckles flaring like embers around his broad grin. "Hey," John replied, and his mouth and vocal cords seemed to obey him just fine. He sat up and looked around.

"Nurse said you should rest," Loeffler warned him. "You got a magic missile in you at that match."

"A what?"

"Yeah, I hadn't heard of it, either. Some kind of spell. McGonagall is having a fit trying to find out who did it. Frerdric was saying it was that kid Holmes - said he was looking up at it and chanting - but Dumbledore put a stop to that, said he could see the magic signature and it wasn't Holmes. Why he couldn't just say who did it, we don't know, so we're not sure we believe him." Loeffler stopped, realizing he was rambling a bit. "Anyway - I was just going to hang out and see when you woke up."

"Yea - I'm all right. Actually, I feel fine." John swung his legs out of the bed and stood, experimentally.

"None of that!" A young witch that John didn't know - not surprising, he usually healed fine on his own, and hadn't been to the infirmary in ages - hurried over and pressed him back into bed. "Nurse said I was to keep you in bed for at least overnight, 'case you have a bad reaction to the magic, and said you weren't to get out of bed."

"What if I have to use the bathroom?" John asked, innocently, and Loeffler snickered.

"Then you let me know, and I'll watch over you." Loeffler laughed, and John shot him a dirty look. The young witch blushed, but gave John one final warning before heading back into the potion room.

"See if she'll hang onto it for you," Loeffler snickered, and John rolled his eyes. "Anyway, I should be getting back - dinner started an hour ago. I'll tell our mates you're all right." He chucked John on his undamaged shoulder and trotted out of the room.

John spent the rest of the evening being very bored. Loeffler came back with Cox an hour or so later, and they joked and laughed for only a few minutes before the young witch hustled them out of the room and told them to leave John to rest. Fredric showed up just as the other two were being hustled out, and John thought he overdid his disappointment at not being able to visit just a little too much - but Fredric never did have much tact.

John tried to read, but the books in the infirmary were meant for much younger children. He tried to peel back the bandages on his shoulder and leg to look at the injuries, but the young witch came back again and slapped at his wrists just as he had started to expose a ragged edge of flesh on his leg. She rebandaged the shoulder and leg more tightly, giving him a small potion 'for the pain.'

"I'm not in pain," John protested. Certainly not as much as he would expect from how the injuries looked - more a dull, throbbing ache that was actually quite thrilling.

"It's also to keep any magic infection out," the witch responded. John was then quite leery of what might actually be in it, but when she narrowed her eyes at him in a way that seemed to threaten forced ingestion, he swallowed it down. It was a pleasing potion, tasting vaguely of spearmint, and sure enough, he started to feel groggy immediately afterwards. He slipped into sleep as the witch pulled the cover up to his neck.

* * *

John tossed in the too-warm bed, his dreams full of air whistling past his ears, bludgers flying at his head, and long gut-churning falls from great heights. He woke as he was about to hit the ground, his eyes flying open as he looked around the (surprisingly) empty infirmary. Dim, diffuse moonlight filtered though the window curtains, casting strange, jagged shadows on the walls.

John looked around the room one more time, decided all was quiet, and lay back down on the bed. One of the twisted shadows chose that moment to step forward, and John jumped a good half-foot off the bed. "Jesus!"

"No, Holmes," the shadow said, smugly, eyes glittering in the dark. The skinny boy stepped closer, his form resolving a little more, but still a creation of dim light and deep shadow.

"What are you doing here?" John asked, trying to tell his thudding heart that it could settle down.

"I came to see you. Aren't you curious about who sent out that missile?"

"The word 'round here says it's you," John replied, warily. There was something very odd about anyone - but especially this boy - visiting him at this hour, in darkness, watching him while he slept.

"Don't be an idiot." Holmes paused. "I mean, more of an idiot than usual. Of course it wasn't me. What reason would I have? You're the only person outside of Slytherin who's even halfway decent to me. Besides, that's a stupid and obvious way to kill someone. If I wanted to kill you, I'd poison your butterbeer."

"Right..." John twitched on the bed. Somehow, this did not make him feel better.

"Which I don't. The person who sent that missile didn't want to kill you, either. You'd be surprised if you looked up the description of the Magic Missile spell in Bartleby's Book Of Offensive Magic. They're using a bit of a different context than we would - wizardly war. The description, to some idiot boy with a grudge with the context of schoolyard pranks, would make it sound like a gnat-bite, annoying and debilitating but hardly damaging." Holmes slid one buttock onto the bed, sitting next to John's hip.

John swallowed. "What are you saying?"

The glitter of Holmes's eyes disappeared as he rolled them briefly. "Oh, good god, am I going to have to spell it out for you? Edward Fredric. He wanted to play, and the best way to do it would be to knock out Gryffindor's best Beater, so that he'd have to sub in."

" _What_?" John asked, shaking his head in disbelief. "Fredric? You're mad."

"Well, ask _him_ why he was carrying powdered wyvren extract under his robes to the game," Holmes snapped, jumping off of the bed. "I'm sure he had an _excellent_ reason he'll share with you." Holmes walked two steps away, then turned. "That's the problem with you Gryffindors." He paused. "Well, one of them, anyway. You trust your fellow Housemates and distrust everyone else. It makes you very easy to manipulate, you know." When he saw John was lost for words, he added, "Timothy Cox is the only real friend you have. Fredric resents you, and Loeffler is in love with you. But he thinks he's straight, and he's going to figure all that out at some point, and is going to do something _very_ mean to you when he does in order to make himself feel all right about it." Holmes spun around, stalking out, muttering "If you'd only _observe_ and _think_ about it - but that's too much trouble, isn't it."

John closed his gaping-open mouth and settled back against the pillows. He looked up at the ceiling, knowing he would not get any more sleep tonight.


	3. Dénouement

Exam time. Crunch time.

Still, John had a brilliant idea for his final project, and it was panning out even better than he hoped.

It had all started when he asked Flitwick about the origins of the Invisibility Charm - after all, it was quite a complex charm, with many intricate gestures and incantations; doing any of them incorrectly would make the spell fizzle. It seemed to John very improbable that anyone could come up with something that complex all at once, and Flitwick had suggested, with a kind smile, that John look into it.

It was a very interesting bit of investigation, indeed, and had sent John into the library for many long nights. This was yet another one; books were stacked about, pages marked with scraps of paper, and he was taking notes on spare scroll.

"Imaginerium profundis," he muttered, flicking his wand, and the inkwell turned an interesting shade of pink. John smiled and took a sip of his butterbeer, then hid it back under the table on the adjacent chair. Food and drink in the library were strictly prohibited, but this late at night, and with some measure of caution, he could get away with it.

"What's your project," a dark voice asked sneeringly in his ear, and John choked on his mouthful of butterbeer, "tacky desk accessories?"

John coughed, getting his throat working properly again. "No, I'm working on the origins of invisibility spells."

"Invisibility spells." Holmes walked past John and sat across from him. John put his hand carefully atop his mug of butterbeer. Holmes was a masterful potionist, certainly, and he had discovered that one particularly effective - or, more likely, particularly enjoyable for him - method of testing his potions was to slip them into John's drinks. He hadn't poisoned John, as per his assurance all those months ago in the infirmary, but he had done just about everything short of that - changing John's hair color, his mood, the tone of his voice, giving him a lizard tongue, and, most recently, causing a pair of horns to grow out of his forehead. After having to endure their removal by the sharp-tongued nurse's assistant, John became very careful of where his drinks were when Holmes was in the vicinity, and had enjoyed three blissfully placid weeks, at least as far as bizarre changes to his body were concerned.

"Really," Holmes continued, "if you want to make someone invisible, a potion works far more reliably."

"You can't use a potion on an inanimate object," John pointed out.

"No, but you can bloody well do away with the thing entirely," Holmes replied, frowning.

John grinned. Holmes was rattled, and that was a rare occurrence. "Admit it, there's some use for charms."

"If you're a complete tit," Holmes grumbled. "What is this mess?" He waved his hand at John's books.

"I'm researching the evolution of the invisibility charm," John replied, warming up to the subject. "The color-change charm, was one of the early charms that fed into it." He leapt up, walking over to the stacks and pulling out a book he had gone through earlier, flipping to the relevant diagram. He brought the book back to the table and pointed to it. "See? Color change requires a fundamental alteration of how the object reflects light. So from there, having it not reflect light at all..."

Holmes snorted. "If it doesn't reflect light at all, it's black, not invisible. Idiot."

"Yes, that's where the projection spell comes into play," John replied, triumphantly. "A local projection 180 degrees to the observer, and the black object shows what's behind it. Effectively, invisibility." John drained his butterbeer, satisfied he had finally won a discussion with Holmes.

The boy in question leaned forward, a grin sliding into place on his face. "That simple, eh."

"Yes," John replied, uncertainty setting in. He didn't like the look of that grin.

"How did your butterbeer taste?" Holmes purred.

John looked down at the empty mug under the table. Oh, bloody _hell_ , he had left Holmes alone for nearly twenty seconds near it! "What did you put in it?" John sighed.

" _My_ final project." The grin was widening, Cheshire-Cat-like.

"Which was?"

"Lust potion." Holmes sat back, lacing his long fingers over his stomach.

"Oh, you're taking the piss." Please, John thought, let him be taking the piss.

"Why would I do that?" Holmes looked offended. "It's my _final project_. I want a good grade."

John stood, hastily piling up his books, pulling his notes together. "Hell, I have to get back to my room..."

"The room you share with Loeffler?" Holmes's grin turned particularly mischievous, and John rubbed his forehead. No, he couldn't do _that_. "It will last a full hour," Holmes continued. "It's fairly potent, as well, since _I_ made it. I'd advise we sneak out to the orchard until it wears off."

"We?" John snorted. "No f..." he looked around, quickly, "No way. I'm going by myself."

"This is _my_ potion and _my_ final project," Holmes replied, leaning forward, his eyebrows coming together in irritation. "I'm coming with you to make sure it works. Now let's get out of here before you start humping Filch's leg."

John frowned, but it was true that he could _not_ stay here. Like he didn't have enough problems with lust already, being fifteen and having a penis. He could already feel something stirring inside of him, and he had to swallow rising panic. He grabbed his notes, walked quickly out of the library, and scuttled down the hallway, kicking off his shoes to make less noise on the stone floors. He tucked into alcoves whenever he heard the clatter of shoes, waiting for Flitwick (who was on patrol tonight, thank whatever good fortune was in the universe - he was the most easily evaded of the staff), or Filch, or Snape on a random student-terrifying tear, to move on.

Finally, John made it out to the orchard, in the clean air, with soft dirt between his toes. He stood up against a tree, breathing a sigh of relief, dropping his notes on the ground and his shoes atop.

"Nicely done," Holmes murmured, next to him. "You must sneak out often."

"Oh, piss off, you arsehole," John sighed, closing his eyes and rubbing them. "I'll probably get in trouble, thanks to you."

"You're welcome." John could hear Holmes's grin. "But... well, what a pity. In trouble for nothing. It seems my potion was a failure."

John opened his eyes, ready to laugh the whole episode off - and the laugh died in his throat. Holmes was not six inches away, blue-green eyes bright and peering intently at John. His face was lean, intent, but the lips were full and appealing - and oh, god, the potion _had_ worked, hadn't it. John's heart was thudding, his mouth was dry, and he felt urges to do things he hadn't the proper words for - but with the person Dumbledore had sent him to look after, his charge, his responsibility - a boy just turned twelve, and John so close to being an adult? Oh, this was sick...

"Ah," Holmes licked his lips, "maybe it worked after all?"

There was no resisting it, then, and John put his lips on Holmes's, pressing the two of them together, the warmth and softness of Holmes's mouth stirring him in distressing ways. He had never kissed anyone before, not properly, and he was sure Holmes had not, either; they made a mess of it, lips every which way, teeth banging into each other, tongues tangling oddly, but it all fed John's potion-induced lust, and soon he had Holmes on the ground. He rubbed his erection against Holmes's leg, the other boy gasping into his mouth as he rubbed his own erection against John's body, and there was only Holmes and his wet dark mouth and his body hot against John's, and a burst of pleasure, moaning, making a mess of his trousers...

"I knew it would work," Holmes panted into John's ear. "Well, we have about half an hour left..."

* * *

John stood in the headmaster's office, his leg jiggling. He had requested the meeting, this time - and he was not looking forward to it, not at all. He would be in trouble. He wondered if he might even be expelled. But he could not just pretend it hadn't happened - that he hadn't actually tangled tongues with the boy he had been charged with looking after. He was almost an adult, now, and should damn well start acting like it.

"Why, hello, my dear boy," Dumbledore said brightly as he walked in. "Excellent job last week; you beat Slytherin rather soundly. No residual soreness from your injuries?"

"None to speak of, but that's not what I..."

"Wonderful," Dumbledore enthused, sitting behind his desk. "I heard from Flitwick, too, that your Charms final was brilliant. I'm very pleased with your progression."

"Yes, well, I..."

"I also heard from Professor Snape that you've been a fantastic mentor for young Holmes. Not that he'd say so in so many words," Dumbledore winked at John, "but I can translate from 'Snape' to 'human,' after all these years."

"Yes, that's exactly what I..."

"It's been lovely speaking with you, John, but I really have rather a lot of work to do. Go on, you'll be late for your practice. You'll win the Quidditch Cup this year if you beat Ravenclaw in the last game."

John found himself outside of the Headmaster's stairwell, his head spinning. He had just been rather soundly dismissed. This made no sense. He would have to try again, some other time, make Dumbledore understand that something quite bad had happened...

In the meantime - Dumbledore was right. He would be late for practice if he didn't hurry. He sprinted up to his room to grab his kit.

Practice was brutal. John was in no mood, and so he played as if it were a championship game, bashing the bludgers with all of his strength until his arms ached. He brushed off Loeffler's invitation to go with him and Cox to Hogsmeade afterward. John felt an acute need to be alone, and so took his broom and walked past the pitch, up the hill behind the stands, and sat, his knees drawn to his chin, as the sun slowly sank down in the sky.

It was close to the horizon, bright enough to make John's eyes water, when he heard someone walk up beside him and sit. John didn't have to look; he could, he was vaguely annoyed to notice, recognize who it was from the dusky, spicy smell. "Hello, Holmes."

"Watson." The boy sat down next to John. They sat together, saying nothing, until the sun touched the distant hills and started to slip behind them.

"Garlic," Holmes said, quietly.

"What are you on about," John sighed. He was in no mood for riddles.

"Strong taste of garlic." Holmes paused. "You didn't read my final project report."

"Didn't need to," John replied, bitterly. "I lived it."

"You should have read it," Holmes replied, airily. "The lust potion requires rather a hefty dose of _Allium sativum_. Doesn't work without it."

"My butterbeer didn't taste like garlic," John said, rolling this datum around in his head.

"No," Holmes replied, simply.

"There was no lust potion." John sighed, feeling something rather uncomfortable happen inside of him.

"No," Holmes repeated. "There never was." John heard a whisper of cloth as Holmes turned his head. "I knew you would never kiss me if it were up to you. You have some strange idea that it would be in conflict with what you promised to Dumbledore. So I gave you a convenient excuse."

"Go fuck yourself," John growled, startling even himself with the bitterness in his voice.

"What is your problem?" Holmes asked, annoyed. "I liked it, you certainly seemed to like it."

"You lied to me," John said, finally turning to face Holmes. The boy's face was ruddy in the light of the setting sun. "Just another joke, eh?"

"You lied to yourself," Holmes replied, evenly. "You don't like me. All Slytherins are evil. I'm too young. Lies."

John licked his lips, which felt oddly dry. "Holmes...."

"Sherlock." The response was firm.

"Sherlock." John rolled the name around in his mouth. It tasted rather good. Interesting, different, a mouthful to be careful with. Like the owner.

"You want to do it again, I can tell," Sherlock said, smiling a disturbingly young boy's smile. "I do, too."

John looked carefully at Sherlock. Was this all some elaborate prank? Worse had been done, he knew. But Sherlock was a loner, a boy more on the receiving end of pranks than the giving end. John knew all too well, having extricated Sherlock from the aftereffects of them a time or two. Sherlock's pranks had been immediate, straightforward - potions to do strange things to John.

Or to make him do what he had always wanted to do.

John put his hand out, placing it on Sherlock's cheek. The boy's face was warm, his skin soft, and he leaned into John's touch, closing his eyes and parting his lips. John leaned forward, putting his lips to Sherlock's. The kiss was more deliberate this time, slower, and John _felt_ Sherlock's lips very acutely. He moved his lips on Sherlock's, stroking them, exploring their softness, the faint taste of orange juice still on them...

"Well, now, isn't this sweet," a deep voice said, not two feet behind them. John and Sherlock both jumped, guiltily, and John looked up at the black-robed figure of Snape behind him.

"Are you _corrupting_ my students, Watson?" Snape growled, his eyebrows coming down to a point over his nose.

"No, sir... I was just.. after practice... watching the sunset... fresh air..." John stumbled over his words as he grabbed his broom and straightened his practice robes.

"How kind of you. My Slytherins don't need any of your _fresh air_ ," Snape snapped. "Twenty points from Gryffindor, and it will be thirty if you aren't back in your rooms in five minutes."

John hurried down the hill, running towards the castle walls. He risked a quick glance back. Snape stood, hands on Sherlock's shoulders, cloak flapping in the breeze. The professor resembling nothing less than a giant black crow, holding his fledgling offspring before him, protecting him from predators.


	4. Epilog

John sat next to the window, looking at the bright spring sun shining on the grass. Summer break was so close - one more day, and he would be gone. He could play as long as he liked, sleep as long as he liked - his time his own, for those few precious weeks.

It was strange to be in the Gryffindor dormitory alone; the walls that normally echoed with the voices of a multiplicity of students were as silent as stone really should be. His parents were at a conference, and would not be back in time to pick him up from the train station on the Hogwart's Express's normal schedule. Dumbledore had told him he would arrange a ride back to London for John with Hagrid, so John merely had to amuse himself for two days.

Not a difficult thing for a boy to do, amuse himself while alone at a magic castle with large, verdant grounds. And a flying broomstick.

A bit of loneliness had hit, however, and so he sat at the window, looking over the pitch that was typically full of activity, thinking about how the next season of quidditch would be his last - at least, his last as a Hogwart's student - and he would be _graduating_... an insane thing to contemplate.

John turned his head quickly at the sound of a foot scraping on the stone floor. "Sherlock," he said, startled, "shouldn't you have left on the train?"

"Hid," the boy said, simply. He was wearing his travel robes, which did indeed look as dirty as the would if he had been hiding.

"You'll get in trouble." John was wearing Muggle clothes, as everyone was gone, and jeans were much more suitable for sticking his hands into the pockets, which he proceeded to do.

"I get in trouble all the time, anyway," Sherlock muttered. "I won't be back next year."

"What?" John asked, started.

"Year. Measurement of time. You know, when we all come back to do this... education thing again. Or at least, you will."

"I know what a year is," John replied, stung. "I meant, why aren't you coming back?"

"Mummy decided I'd progress faster with tutoring. I did fourth-year classes this year. Dumbledore said he just can't flex the rules enough to have me take fifth-year classes next year, so it's really the only option."

"Hell," John replied, looking down at his feet. "I'll... miss you." That was one thing John had been rather looking forward to - having another year to just be a student with Sherlock, get in a good place with him, figure out how to properly be mates, not have this strangeness between them that frustrated him and gave him disturbing dreams.

"I'll miss you, too," Sherlock replied, as if reporting on an unimportant weather condition. "That's why I'm here."

"To say goodbye?"

Sherlock snorted, shaking his head. "I'd hardly have to hide and get in trouble just to say goodbye, would I? Think for a minute, would you."

"To insult me, then?" John asked, grinning. There was something fun about this. But Sherlock was in no joking mood, John could tell.

"No," the other boy replied, closing the distance between them with a few quick strides. He was now _very_ close, and John's mouth fell open. They hadn't kissed since the evening they had been caught by Snape. John had to admit, Snape terrified him - and avoiding any of _that_ , well, it reduced the complication in his life.

Complication that was now roaring back with a vengeance, as Sherlock pressed their lips together. They kissed, gingerly, slowly, but John could feel Sherlock had more on his mind; there was something rushed in the movement of his lips, his hand on John's cheek.

Sherlock pulled back, after a moment. "I probably won't see you again. There's something we have to do." His voice was matter-of-fact, but slightly urgent.

"What?" John asked, feeling those disturbing desires that haunted his dreams flitter to the fore.

"Take your clothes off," Sherlock murmured into John's ear, plucking at his shirt.

Rubbing against each other, getting off... the idea was exciting enough to overcome what little good sense John had, and he scrambled out of his clothing. He sat on the large, plush rug to pull his jeans all of the way off, and Sherlock kneeled next to him, shedding his own clothing. They kissed, again, and John had never felt _this_ excited, before - naked, kissing, in the middle of the common room...

Once Sherlock was out of his clothes, he hiked one leg up and straddled John. John tried to pull Sherlock close, but the other boy pulled back. He picked a small bottle up from his pile of discarded clothing.

"I read about this," Sherlock panted, his face flushed, dipping his finger into the bottle. "I'm going to remember you. You have to remember me, too."

What a silly idea, John thought, him forgetting Sherlock, but all thoughts flew out of his head as Sherlock slid a slippery finger into him. He had never conceived of such a thing, but the pleasure was ridiculous, as intense as the eyes on the boy staring at him, mouth slightly open, pushing his finger in, then another, a little keening noise coming from his throat as he moved his fingers. "You like this," he said, finally, his voice strained. He dribbled some of the liquid on the bottle on his own cock, stroking it awkwardly with his left hand.

"Sherlock," John gasped. His erection was leaving smears of precome on his stomach; this felt simply beyond brilliant, but... hell, Sherlock was younger, and John still felt responsible, and this was one _large_ step beyond...

"Please," Sherlock said, and John had never heard the boy _ask_ for anything, not like that, his eyes so wide and _wanting_ \- and yes, John wanted it, too. He nodded, speechless, and Sherlock pulled out his fingers, his face a little relieved.

John gasped at how gapingly empty he suddenly felt - but soon enough, he would be filled, more than before. Both boys were panting as if they had run a marathon, their breaths echoing unnaturally loudly in the quiet room. Sherlock braced himself on both arms, positioning himself, and looked at John. "You won't forget me... you can't." His voice sounded strained, almost desperate.

"I..." John started to say, then closed his mouth at the sounds of footsteps on stone.

 _...saw... this morning, I thought..._ Snape's voice was muffled by layers of stone, his voice barely audible but he was clearly outside of the doorway. _Searched... Slytherin... parents..._

John turned his head at the sound of Sherlock leaping to his feet and stuffing his body back into his clothes. "Got to go," Sherlock hissed. He flung open the window, turned his head to give John an angry, accusing glance, and... suddenly, there was a black crow where Sherlock had been, and it fluttered out of the window.

A banging sound at the door. "Watson, are you in there?" Snape asked, his voice irate.


End file.
